Functional properties of the lysosomal amino acid transporter PQLC2 - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement
Poster De Conférence Année : 2015

Functional properties of the lysosomal amino acid transporter PQLC2

Résumé

The transporter PQLC2 exports cationic amino acids (CAA) derived from lysosomal proteolysis to the cytosol. It is also required for drug therapy of cystinosis (Jézégou et al., PNAS 2012; Liu et al., Science 2012). We previously showed that PQLC2 is electrogenic and sensitive to pH. In this new set of experiments, we investigate the transport mechanism of PQLC2 by the use of the two-electrode voltage clamp technique (TEVC) with a construct that misrouts the protein to the plasma membrane of Xenopus oocytes. We first show that PQLC2 transports one charge per arginine molecule and is not coupled to protons. It is thus most probably a uniporter. In agreement with this mechanism, PQLC2 is very sensitive to membrane potential. Finally and surprisingly, PQLC2 appears to exchange selectively lysosomal arginine for cytosolic cationic amino acids in an electroneutral transport mecanism. This last property supports a selective role of PQLC2 in mobilizing Arg from lysosomes or in regulating lysosomal Arg level.
Fichier principal
Vignette du fichier
2015_GRC_PQLC2_poster_v3 copie.pdf (7.83 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Licence

Dates et versions

hal-04652959 , version 1 (18-07-2024)

Licence

Identifiants

  • HAL Id : hal-04652959 , version 1

Citer

Xavier Leray, Yan Li, Anselm A Zdebik, Bruno Gasnier. Functional properties of the lysosomal amino acid transporter PQLC2. Gordon Research Conference (GRC) on Organellar Channels and Transporters, Jun 2015, West Dover, VT, United States. ⟨hal-04652959⟩
13 Consultations
7 Téléchargements

Partager

More